Genetic Mutation In Butterflies Due to Radiation

Genetic mutations have been noticed in three generations of butterflies from Japanâ€™s Fukushima nuclear plant, scientists says. (Photo : Reuters)

Genetic mutations have been noticed in three generations of butterflies from Japan's Fukushima nuclear plant, scientists says.

Exposure to radioactive material released into the environment has caused mutation in butterflies. Around 12 percent of pale grass blue butterflies that were exposed to nuclear fallout as larvae immediately after the tsunami-sparked disaster had abnormalities, including smaller wings and damaged eyes. They also noticed an increase in leg, antennae and wing shape mutations among butterflies collected following the 2011 Fukushima accident.

The quake-sparked tsunami of March 2011 hit the cooling systems at the Fukushima Daiichi nuclear power plant, causing three reactors to go into meltdown in the world's worst atomic disaster for 25 years.

The scientists had conducted laboratory experiments to show the link between the mutations and the radioactive material. The teams of researchers have been studying that particular species butterfly for more than 10 years.

The insects were bred outside the fallout zone and 18 percent of their offspring displayed similar problems.

According to Joji Otaki associate professor at Ryukyu University in Okinawa, southwestern Japan, the number increased to 34 percent in the third generation of butterflies, even though one parent from each coupling was from an unaffected population.

The researchers collected another 240 butterflies in Fukushima in September last year, six months after the disaster. They noticed that abnormalities were recorded in 52 per cent, which was 'a dominantly high ratio.

The researcher had also carried out a comparison test in Okinawa exposing unaffected butterflies to low levels of radiation, with the results showing similar rates of abnormality,

The findings that were published in the Scientific Reports, an online research journal from the publishers of Nature show that the radionuclides released from the Fukushima Daiichi plant accident were still affecting the development of the animals by damaging their genes, even after the residual radiation in the environment had decayed.

The effects of this radiation were so strong that it forced many people to evacuate. The researchers say that results on the Fukushima butterflies could not be directly applied to other species, including humans.